Our long-range goal is to be able to non-invasively distinguish viable from non-viable embryos by image analysis. As a starting point we propose to use NADH imaging to visualize mitochondrial distribution in the embryos. There is recent evidence that in bovine oocytes stained with Mitotracker Rosamine the mitochondrial distribution is different in oocytes cultured in optimal versus suboptimal media. Initial experiments at the resource have demonstrated that NADH autofluorescence indeed correlates with the Mitotracker signal in freshly excised mouse oocytes. Futhermore, differences in morphology between oocytes is easily observed via two-photon excited NADH autofluorescence. A systematic study of oocyte health as reported by cellular autofluorescence is planned in the near future. 1 DLPC - dilauroyl-sn-glycero-3-phosphocholine, DPPC - dipalmitoyl-sn-glycero-3-phosphocholine, DMPC - dimyristoyl-sn-glycero-3-phosphocholine,